public MuComFrame(byte[] inputBuffer)
{
if (inputBuffer is null)
{
throw new ArgumentNullException(nameof(inputBuffer));
}
if (inputBuffer.Length < 2)
{
throw new ArgumentException("Input buffer must contain at least two elements");
}
//Copy buffer
this.RawBuffer = new byte[inputBuffer.Length];
inputBuffer.CopyTo(this.RawBuffer, 0);
//Decode header
this.Description = MuComFrame.GetFrameDescriptionFromHeader(this.RawBuffer[0]);
this.ID = MuComFrame.GetIdFromFrame(this.RawBuffer);
this.DataCount = MuComFrame.GetDataByteCountFromHeader(this.RawBuffer[0]);
//A read request frame is only two bytes long and does not
if (this.Description == MuComFrameDesc.ReadRequest)
{
this.DataBytes = new byte[0];
return;
}
//Check input frame size
int expectedLength = MuComFrame.GetFrameSizeFromDataCount(this.Description, this.DataCount);
if (inputBuffer.Length < expectedLength)
{
throw new ArgumentException("Input buffer size too small! " + expectedLength.ToString() + " expected but input buffer contains only " + inputBuffer.Length.ToString() + " bytes.");
}
//Create buffer for data bytes and intermediate buffer
byte[] buffer = new byte[this.DataCount + 1];
this.DataBytes = new byte[this.DataCount];
//Reconstruct data from frame
//Buffer[0..8] = Data bytes (first byte will be index)
int dataPos = 0;
int bytePos = 1;
for (int i = 0; i < (this.DataBytes.Length + 1); i++)
{
if (bytePos < 0)
{
bytePos = 6;
dataPos++;
}
buffer[i] = (byte)(this.RawBuffer[dataPos] << (7 - bytePos));
dataPos++;
buffer[i] |= (byte)(this.RawBuffer[dataPos] >> bytePos);
bytePos--;
}
//Copy data
this.ID = buffer[0];
Array.Copy(buffer, 1, this.DataBytes, 0, this.DataBytes.Length);
}